gh-150077:Fix fileobj leak in tarfile.TarFile.zstopen on BaseException

Lib/tarfile.py

@@ -2083,7 +2083,7 @@ def zstopen(cls, name, mode="r", fileobj=None, level=None, options=None,
             if mode == 'r':
                 raise ReadError("not a zstd file") from e
             raise
-        except Exception:
+        except:
             fileobj.close()
             raise
         t._extfileobj = False

Lib/test/test_tarfile.py

@@ -1065,6 +1065,21 @@ class LzmaDetectReadTest(LzmaTest, DetectReadTest):
 class ZstdDetectReadTest(ZstdTest, DetectReadTest):
     pass
 
+@support.requires_zstd()
+class ZstdOpenTest(unittest.TestCase):
+    """
+    See: https://github.com/python/cpython/issues/150077
+    """
+    def test_zstopen_closes_fileobj_on_base_exception(self):
+        fileobj = unittest.mock.Mock()
+        with unittest.mock.patch("compression.zstd.ZstdFile",
+                                 return_value=fileobj), \
+             unittest.mock.patch.object(tarfile.TarFile, "taropen",
+                                        side_effect=KeyboardInterrupt):
+            with self.assertRaises(KeyboardInterrupt):
+                tarfile.TarFile.zstopen("foo.tar.zst")
+        fileobj.close.assert_called_once()
+
 class GzipBrokenHeaderCorrectException(GzipTest, unittest.TestCase):
     """
     See: https://github.com/python/cpython/issues/107396

Misc/NEWS.d/next/Library/2026-05-19-18-25-00.gh-issue-150077.zstopen-close.rst

@@ -0,0 +1,4 @@
+Fix ``tarfile.TarFile.zstopen`` to close the underlying zstd file object
+when opening the tar archive is interrupted by a :exc:`BaseException`
+subclass such as :exc:`KeyboardInterrupt`.
+